NOTE This instance is currently the only one using an inline outer
check. If This behaves well, it could be possible to put checks for valid
indices inside the outerCheck function. (Currently disabled, as the compiler
chokes on four-way alignments).

NOTE This instance is currently the only one using an inline outer
check. If This behaves well, it could be possible to put checks for valid
indices inside the outerCheck function. (Currently disabled, as the compiler
chokes on four-way alignments).